Electrodeposition of nickel



United States Patent 2,757,133 ELECTRODEPOSITION OF NICKEL Wilbur J.Shenk, Jr., Shaker Heights, Ohio, assignor to The Harshaw ChemicalCompany, Elyria, Ohio, a corporation of Ohio No Drawing. ApplicationJune 10, 1952,

Serial No. 292,725

'17 Claims. (Cl. 204-49)" This invention relates to electrodeposition ofnickel, and more specifically to the use of certain addition agentswhich effectively enhance brightness and improve ductility.

It is recognized that prior to the present invention a great variety oforganic addition agents have been used or proposed for use for theproduction of bright or semibright nickel deposits. Some of these haveproved to be of commercial value, while others have failed because oftheir sensitivity to impurities or failure to continue pro ducing gooddeposits over sufliciently long periods of time. Some of the proposedaddition agents have not been commercialized merely because otheraddition agents were found to be somewhat superior. Such considerationsas the rate of consumption in the plating solution, the difiiculty ofanalyzing the solution or otherwise determining the concentration ofbrightener, and the build-up of the concentration of degradationproducts are important in the choice of brightening addition agents.

The present invention has to do with the use, either as the solebrightening addition agent or as a cooperating addition agent for usewith other brighteners, of a class of compounds, one representative ofwhich is a compound known as dibenzenesulfonamide or dibenzenesulfonylamine and having the formula,

0 H o Q ti ti Other examples of the class are:

TABLE I 1) Trichlorodibenzenesulfonamides- Cl2CsHzSO2NHSO2CsH4C1 (2)Tetrachlorodibenzenesulfonamides- ClaCeHsSOzNHSOzCsHsClz (3Di-B-naphthalenesulfonamide- CIOH'ISOZNHSO2C10H7 (4)2,2,4,4,6,6'-HeXachlorodibenzenesulfonamide- ClsCsHzSOzNHSOzCsI-IzCls(5) Pentachlorodibenzenesulfonamides- ClaCsHzSOzNHSOzCsHaClz (6)Methyldichlorodibenzenesulfonamides- Cl2CsH3SO2NHSO2CsH4CH3 (7)2,4,6-Trichl-orodibenzenesulfonarnide- ClaCsHzSOzNHSOzCeHs (8) 2,5-Dichloro-3 -sulfamyldibenzenesulfonamide- C12C6H3S02NHSO2C6H4SO2NH2 9Disulfonilamide-NHzCsH4SO2NI-ISO2CsH4NHz (10)N-phenylsulfonyl-fi-naphthalenesulfonamide- 2,757,133 Patented July 31,1956 I CC 2 (1 l) Di-p-toluenesulfonamide- CH3C6H4SO2NHSO2C6H4CH3 l2)4-Methyldibenzenesulfonamide- CeH5SO2NHSO2CsH4CI-Is l 3) N,N'-bis(phenylsulfonyl) -m-sulfamylbenzarnide- CsHsSOzNHSOzCsHrCONHSOzCsHs l4)Dicumenesulfonamide (CH3)2CHCsH4SO2NHSOzCsI-I4CH(CH3)2 l 5)4-Ethyldibenzenesulfonamide- CBHSSOZNHSOZCGHCZHE 16)4,4-Dicarboxyldibenzenesulfonamide- COOHCsH4SO2NHSO2CsH4COOH l7)2,2,4,4'-Tetramethyldibenzenesulfonamide- CH3 zCsH's'SOzNHSOzCsHs (CH3 218 Dichlorodibenzenesulfonamidescncsrnsomnsozcsm (19)4-Fluorodibenzenesulfonamides- FCsH4SO2NHSO2CsH5 (20)4-Carboxyldibenzenesulfonamide- CsH5SO2NHSO2CsH4COOH (21) N,N' bis(phenylsulfonyl) 1,3 benzenedisulfonamide-CsH5SO2NHSO2CBH4SO2NHSO2C6H5(22)N,N'-bi-s(dichlorophenylsulfonyl)-1,3-benzenedisulfonamidcs-ClzCGH3SO2NHSO2CGH4SOzNHSOaCaI-IzClz(23) N,N bis (phenylsulfonyl) 4,4diphenyldisulfonamide-CsHsSOzNHSOaCsH4CeH4SO2NHSO2CsH5 (24)p,p-Oxy-bis(dibenzenesulfonamide)- (26) N,N-bis(2,4,6-trichlorophenylsulfonyl)-1,3-benzenedisulfonamide- (27) N,N'-bis(p-tolylsulfonyl) 4,4 diphenyldisulfonamide-CH3CsH4SO2'NHSO2CsH4CsH4SOzNHSOzCsHtCHa 28)N-ethylsulfonylbenzenesulfonamide- CsHsSOzNHSOzCHzCHs (29)N-vinylsulfonylbenzenesulfonamide- CsH5SOzNHSO2CH=CH2 (30)N-(n-butylsulfonyl)benzenesulfonamide- CsHsSO2NHSO2C4H9 (31 N-(n-laurylsulfonyl -benzenesulfonamide- CsH5SO2NHSO2C12H25 (32)Di-a-toluenesulfonamide- C6H5CH2SO2NHSO2CH2C6H5 3 3N-benzylsulfonylbenzenesulfonamide- CsHsSOzNHSOzCHzCsHa (34)N-ethylsulfonyldichlorobenzenesulfonamides- ClzCsHsSOzNHSOzCzHs (35N-methallylsulfonylbenzenesulfonamide- CeH5SO2NHSOzCH2C(CH3 =cn2 (3 6)N-methyl-sulfonylbenzenesulfonamide- CsHsSOzNI-ISOzCI-Is (37)Dimethanesulfonamide-CHsSOzNI-ISOzCI-Ia (Inoperative) (38)Didodecanesulfonamide (inoperative) (39) N,N'-bis(phenylsulfonyl)- 1,5naphthalenedisulfonamide somnsmQ CrzHzsSOzNI-ISOzCrzI-Izs somnsoQ (40)N,N'-bis (phenylsulfonyl)3,3'-benzophenonedisulfonamide-CsHsSOzNI-ISOzCsHsCOCsHaSOzNHSOzCsI-IaPhSOzNHSOzPh has a pH of 1.3 in tenth normal solution whereas PhSOzNHzis only about as acidic as phenol. Again, they are very soluble inwater. For example, PhSOzNHSOzPh is soluble in water at 20 C. to theextent of about 50 grams per liter, while PhSO2NH2 is soluble under thesame conditions only to the extent of about 3 grams per liter. Thissolubility difference increases in importance as one considers nuclearsubstitution products of benzenesulfonamide which have less solubility.Thus 2,5-dichlorobenzenesulfonarnide, ClzCsHsSOaNI-Iz, appears to havepromise as a scratchfilling carrier in certain bright baths, but its lowsolubility, 0.5 g./l. in Watts bath solution, severely limits itsusefulness. On the other hand, 2,5-dichlorodibenzenesulfonamide,ClzCsHsSOaNHSOzCeHB, has a solubility of approximately 30 g./l. in theWatts bath, thus permitting its use over a wide range of concentrations,and it has been found to be an excellent scratch-filling carrier.

It has been established that 2,5-dichlorodibenzenesulfonamide is slowlyconverted principally to dibenzenesulfonamide by hydrogenolysis duringthe plating operation, and

it appears that the superior leveling properties of the bath containingthis compound are in some way related to this reaction which ispresumably taking place catalytically on the freshly deposited nickelsurface.

If one tries to increase the degree of halogenation to say2,2,5,5-tetrachlorodibenzenesulfonamide low solubility (in this caseabout 1 g./l.) again becomes a limiting factor but this can be overcomeby using a compound containing two disulfonamide groups. Thus, N,N-bis-(2,S-dichlorophenylsulfonyl) 1,3 benzenedisulfonamide,

compounds for use in accordance with the invention:

TABLE II n and n each indicating an integer from 0 to 3 and the sum of12 plus n not exceeding 3.

SOzNHSOa SOQNHSOZ n and n each indicating an integer from 0 to 3 and thesum of n plus n not exceeding 6.

n and n each indicating an integer from 0 to 3 and the sum of n plus 11'not exceeding 6.

n and n each indicating an integer from 0 to 3, and the sum of n plus 11not exceeding 6.

n and 11 each indicating an integer from 0 to l. (7)C6H5SO2NHSO2C6H4COCsHtSOzNHSOzCeHs.

These compounds indicated in Tables 1 and II are examples of the classof disulfonamides which produce semibright to bright deposits when usedin the acid nickel plating solution as the sole brightener, for examplein a solution of the Watts type, which might, for example, contain 240grams per liter of nickel sulfate hexahydrate, 40 grams per liter ofnickel chloride hexahydrate, and 40 grams per liter of boric acid,remainder water. It is to be understood that such a nickel plating bathwould normally contain an anti-pit agent of the wetting-agent type, suchfor example as sodium lauryl sulfate or other aliphatic sulfate having 8to 18 carbon atoms or mixtures thereof, and that the same might bepresent within the limits of solubility but preferably about 0.1 to 0.5grams per liter. The anti-pit agent is not always necessary, since thebath sometimes produces pit-free deposits without it, and sometimes thedegree of pitting is such as can be tolerated even though some pits arepresent.

As above indicated, the novel class of compounds can be effectively usedin combination with a wide variety of other brighteners, with the resultthat there is produced bright, ductile deposits having good throwingpower and capable of being operated trouble-free for long periods oftime. Examples of such cooperating brighteners are as follows:

TABLE III Ethylene cyanohydrin Vinyl pyridine TriaminotriphenylmethaneN-Methylquinaldinium methyl sulfate Allyl alcohol Succinonitrile (7)Cyclohexanone oxime (8) Butyraldoxime (9) Benzaldehyde (10)N-Methylisoquinolinium methyl sulfate (11) N-methylpyridinium methylsulfate (12) Pyruvic aldehyde (13) Barbituric acid The disulfonamidescontemplated by the invention for use in nickel plating solutions are ofthe character indicated by the foregoing examples, that is, they arecompounds of the type:

enema where (1) R and R both may be aromatic radicals, or (2) R may bean aromatic radical While R is an aliphatic radical, or (3) both R and Rmay be aliphatic or aryl substituted aliphatic radicals. The aromaticradicals should in all instances be limited to not more than nuclearcarbons and may carry one or a plurality of substitucnts of the classchlorine, bromine, fluorine, methyl, ethyl, carboxyl, sulfamyl,R'SOzNHSOzR,

OR'SOzNI-ISOzR and SOzNHSOaR. The aliphatic radicals, when both R and Rare aliphatic, must contain at least 2 but should not contain more than18 carbon atoms, must have at least one unsaturated carbon to carbonbond, which, however, may be in an aryl substituent, and may carry oneor a plurality of substituents of the class consisting" of chlorine,bromine fluorine, methyl, ethyl, carboxyl, R'SO2NHSO2'R, CHzRSOzNHSOaR,OR'SOzNHSOzR and SO2NHSO2R. When R is aromatic and R is aliphatic, Rshould be limited to not more than 10 carbon atoms and R may besaturated or unsaturated and may contain froml to 18 carbon atoms.Either R or R in that case may be substituted by chlorine, bromine,fluorine, carboxyl or sulfamyl, aryl having not more than 6 carbonatoms, R'SOaNHSOzR, CHzR'SOzNHSOz'R, OR'SOzNI-ISOzR or SOzNI-ISOzR. Inother Words, R is an organic radical of the class consisting of aromaticradicals having not more than ten nuclear carbon atoms and aliphaticradicals having at least one unsaturated carbon to carbon bond, and R isselected from the class consisting of aromatic radicals having not morethan ten nuclear carbon atoms, aliphatic radicals having from i to 18carbon atoms, aryl substituted aliphatic radicals having from 7 to 11carbon atoms, and radicals of the formula RSO2NHSO2R.

In general, the concentration of the disulfonamide should be from 0.2 to6 grams per liter, preferably from 0.5 to 6.0 grams per liter when usedas the sole brightening addition agent in a Watts type bath to produce asemi bright deposit. When used in conjunction with aryl sulfonic acids,sulfonates, sulfonamides or sulfirnides, which are themselves effectiveto produce semi-bright deposits and, in cooperation with auxiliarybrighteners such as those listed above, to produce fully brightdeposits, the concentration may vary from a very small amount, forexample 0.1 gram per liter up to 6 grams per liter, and may be expectedto perform its function to a degree in proportion to its concentration.The auxiliary brightening addition agents such as ethylene cyanohydrinand others listed above may be present in various concentrations,ordinarily quite small, and up to such concentration as tends toembrittle the deposit excessively. Suitable concentrations of variousauxiliary brightening addition agents are as indicated in the specificexamples hereinafter set forth.

The constituents of the bath according to the preferred practice of theinvention are: 1) water; (2) nickel sulfate, nickel chloride, or nickelsulfate with nickel chloride; (3) a disulfonamide of the class aboveindicated or a plurality thereof; (4) a wetting agent such as sodiumlauryl sulfate or a mixture of aliphatic sulfates having from 8 to 18carbon atoms, the wetting agent being optional; and (5) an auxiliarybrightening addition agent such as those listed above, the auxiliarybrightening addition agent also being optional. An additionalingredientof the solution which is desirable is a buifering agent suchas boric acid, formic acid, or the like.

It Will be noted that in respect to major constituents, the solutionsare similar to the Well-known all sulfate, all chloride, andsulfate-chloride 01' Watts type acid nickel plating solutions. It willbe noted also that the auxiliary brighteners such as ethylenecyanohydrin and others listed therewith above are, for the most part,con ventional auxiliary brighteners for use with aromatic sulfonic acidsand sulfonamides. The essence of the 6 present invention is in the useof dibenzenesulfonamide and/ or other compounds listed above, it havingbeen discovered that this class of compounds, either as. the solebrightening addition agent or as a cooperating brightening additionagent, imparts to the bath unexpected properties of bright throwingpower, ductility and smoothness. A further important feature of theinvention is the use of dibenzenesulfonamide and the other members ofits group as above indicated, in solutions which already containaromatic sulfonic acids, sulfonates or sulfonamides as a partialsubstitute for those compounds for the purpose of imparting theunexpected properties in dicatedabove. In other words, thedibenzenesulfonamide type of addition agent imparts superior brightthrowingpower, ductility and smoothness to bright plating solutions ofthe type wherein principal reliance is placed on a combination of amononuclear aromatic sulfonyl compound and an auxiliary brighteningagent. In conventional solutions, the aromatic sulfonate, for examplenaphthalene sulfonate, is often referred to as a carrier, while anauxiliary brightener such as triaminotriphenylmethane is referred to asthe brightener. In this terminology the disulfonamide is useful eitheras carrier or as a partial substitute for the usual type of carrier toimpart enhanced bright throwing-power, ductility and smoothness. Again,Where the disulfonamide is used without the brightener, it producessemi-bright deposits having good semi-bright throwing power, excellentductility and a good smoothing action.

The preferred basic solutions in connection with which the invention isrealized are as follows:

All sulfate NiSO .7H20 s to 400 g., preferably 200 to 300 g. Boriq a'cid0 to 60 g., preferably 10 to 40 g. Wetting agent (e. g., soiium laurylsulfa 0' to 0.5 g'., preferably 0.05 to 0.2 g. H20 to make 1009 cc.

All chloride 50 to 250 g., preferably 100 to 200 g. 0 to 60 g.,preferably 10 to 40 g.

NiCl2.6HeO r Boric acid Wetting agent (e. g.,

solium lauryl sula 0 to 0.5 g., preferably 0.05 to 0.2 g. H2O to make1000 cc.

Wetting agent (e. g.,

sotdium lauryl sul- 13261;) 155128166356. 0 to 0.5 g., preferably 0.025to 0.2 g.

To each of the foregoing basic solutions may be added a quantity of thedisulfonamide and, if full brightness is desired, a quantity of abrightener and, optionally, a carrier of the aromatic sulfonate oraromatic sulfonamide type.

The following specific examples of plating solutions will serve toillustrate the invention, it being understood that the various exampleslisted above are interchange able in the following solutions withaddition agents of the same class (carrier or auxiliary brightener) andgive similar results although some of the compounds of Table I do givevery superior results especially in some instances as herein elsewhereindicated.

H2O to make one liter.

EXAMPLE II (Semi-Bright) NiSO4.6I-Iz grams 240 NiCl2.6H2O do 40 H3BO3 do40 Dibenzenesulfonarnide do- 6 pH 3.5 Temperature F 140 Cathode currentdensity A. S. F 40 H2O to make one liter.

EXAMPLE III (All Chloride-Bright Semi-Bright) NiClz.6H2O grams 300 HsBOzdo 50 Dibenzenesulfonamide do 2 pH 3.5 Temperature F 140 Cathode currentdensity A. S. F 40 H2O to make one liter.

EXAMPLE IV (Bright) NiSO4.6H2O grams 240 NiCl2.6I-I2O do 40 1131303 do40 Dibenzenesulfonamide do 0.5 Ethylene cyanohydrin do 0.24 pH 3.5Temperature F 140 Cathode current density A. S. F 40 H2O to make oneliter.

EXAMPLE V (Bright) NiSO4.6HzO grams 240 NiClz.6HzO do 40 HsBOa do 40Dibenzenesulfonamide do 0.5 Naphthalene disulfonate do 4Triaminotriphenyl methane do 0.005 pH 3.2 Temperature F 140 Cathodecurrent density A. S. F 40 E20 to make one liter.

EXAMPLE VI (Bright) NiSO4.6H2O grams 240 NiCl2.6H2O d0.. 40 H3303 do 40Dibenzenesulfonamide do 0.5 Benzaldehyde do 0.4 pH 3.5 Temperature F 140Cathode current density A. S. F 40 H2O to make one liter.

EXAMPLE VII (Bright) NiSO4.6I-I2O grams 240 NiCl2.6I-I2O do 40 H3BO3 do40 Naphthalene benzene disulfonamide (N-phenyl sulfonyl-Z-naphthalenesulfonarnide "grams" 0.3

Triaminotriphenyl methane do 0.005 pH 3.5 Temperature F 140 Cathodecurrent density A. S. F 40 B20 to make one liter.

EXAMPLE VIII (Semi-Bright) NiSO4.6H2O "grams" 240 NiCl2.6H2O d0 40I-I3BO3 do 40 ClzCsI-IsSOzNHSOzCsI-MCI d0.. 0.5 pH 3.5 Temperature F 140Cathode current density A. S. F 40 H2O to make one liter.

Having thus described my invention, what I claim is:

1. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent of the formulaR-SO2NHSO2R, where R is an aromatic radical having not more than tennuclear carbon atoms and R is selected from the class consisting ofaromatic radicals having not more than ten nuclear carbon atoms,aliphatic radicals having from 1 to 18 carbon atoms, including at leastone unsaturated carbon to carbon bond, aryl substituted aliphaticradicals having 7 to 11 carbon atoms, radicals of the formula R"SO2NHSO2radicals of the formula RR"-SO2NHSOz-R"', radicals of the formulaRORSO2NHSO2R and radicals of the formula RCH2R-SO2NHSO2-R", R, R" and Roccurring in said last four radicals, indicating aromatic radicalshaving not more than ten nuclear carbon atoms, said addition agent beingpresent to the extent of from 0.1 to 6 grams per liter.

2. The process of electroplating metallic surfaces by electrolyticdeposition from nickel salt solution which comprises passing current tosaid metallic surface as a cathode through said solution containing asan additive a compound of the formula R-SO2NHSO2R, where R is anaromatic radical having not more than ten nuclear carbon atoms and R isselected from the class consisting of aromatic radicals having not morethan ten nuclear carbon atoms, aliphatic radicals having from 1 to 18carbon atoms including at least one unsaturated carbon to carbon bond,aryl substituted aliphatic radicals having 7 to 11 carbon atoms,radicals of the formula R--SO2NHSO2 radicals of the formula radicals ofthe formula RORSO2NHSO2R and radicals of the formula RCH2R"SO2NHSO2-R",R, R and R' occurring in said last four radicals indicating aromaticradicals having not more than ten nuclear carbon atoms, said additionagent being present to the extent of from 0.1 to 6 grams per liter.

3. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having the formulawhere R and R are aromatic radicals having not more than ten nuclearcarbon atoms, said addition agent being present to the extent of from0.1 to 6 grams per liter.

4. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having the formulawhere R is an aromatic radical having not more than ten nuclear carbonatoms and R is an aliphatic radical having from 1 to 18 carbon atoms andcontaining at least one unsaturated carbon to carbon bond, said additionagent being present to the extent of from 0.1 to 6 grams per liter.

5. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having the formulawhere R, R and R" are aromatic radicals having not more than ten nuclearcarbon atoms, said addition agent being present to the extent of from0.1 to 6 grams per liter.

6. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having the formulawhere R, R', R and R' are aromatic radicals having not more than tennuclear carbon atoms, R and R" being connected through nuclear carbon,said addition agent being present to the extent of from 0.1 to 6 gramsper liter.

7. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having the formulawhere R is an aromatic radical having not more than ten nuclear carbonatoms and R is an aryl substituted aliphatic radical having from 7 to 11carbon atoms, said addition agent being present to the extent of from0.1 to 6 grams per liter.

8. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having theformula:

21 and n each indicating an integer from to 3, and the sum of n plus nnot exceeding 3, said addition agent being present to the extent of from0.1 to 6 grams per liter.

9. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having theformula:

n and n each indicating an integer from 0 to 3, and the sum of n plus nnot exceeding 6, said addition agent being present to the extent of from0.1 to 6 grams per liter.

10. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having theformula:

@s OINHS O2S olNns 02G 01.

n and n each indicating an integer from 0 to 3, and the sum of n plus itnot exceeding 6, said addition agent being present to the extent of from0.1 to 6 grams per liter.

11. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sul- Gin fate, nickelchloride and mixtures thereof, together with an addition agent havingthe formula:

n and 11' each indicating an integer from O to 3, and the sum of 11 plusIt not exceeding 6, said addition agent being present to the extent offrom 0.1 to 6 grams per liter.

12. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having theformula:

said addition agent being present to the extent of from 0.1 to 6 gramsper liter.

13. An acid, nickel electroplating solution comprising a nickelelectrolyte of the class consisting of nickel sulfate, nickel chlorideand mixtures thereof, together with an addition agent having theformula:

@somnso,

Q}somnso= 16. The invention as defined in claim 1 wherein said additionagent is C6H5SO2NHSO2C6H4OCGH4SOZNHSOZCGH5 17. The process ofelectroplating metallic surfaces by electrolytic deposition from nickelsalt solutions which comprises passing current to said metallic surfaceas a cathode through said solution containing as an additive SOQNHSO CHCH:

said additive being present in said solution to the extent of 0.1 gramper liter.

References Cited in the file of this patent UNITED STATES PATENTS2,191,813 Brown Feb. 27, 1940 2,467,580 Brown Apr. 19, 1949 2,644,788Shenk July 7, 1953 2,644,789 Shenk July 7, 1953

1. AN ACID, NICKEL ELECTROPLATING SOLUTION COMPRISING A NICKELELECTROLYTE OF THE CLASS CONSISTING OF NICKEL SULFATE, NICKEL CHLORIDEAND MIXTURES THEREOF, TOGETHER WITH AN ADDITION AGENT OF THE FORMULAR-SO2NHSO2-R'', WHERE R IS AN AROMATIC RADICAL HAVING NOT MORE THAN TENNUCLEAR CARBON ATOMS AND R'' IS SELECTED FROM THE CLASS CONSISTING OFAROMATIC RADICALS HAVING NOT MORE THAN TEN NUCLEAR CARBON ATOMS,ALIPHATIC RADICALS HAVING FROM 1 TO 18 CARBON ATOMS, INCLUDING AT LEASTONE UNSATURATED CARBON TO CARBON BOND, ARYL SUBSTITUTED ALIPHATICRADICALS HAVING 7 TO 11 CARBON ATOMS, RADICALS OF THE FORMULAR"-SO2NHSO2-R"'', RADICALS OF THE FORMULA RR"-SO2NHSO2-R"'', RADICALS OFTHE FORMULA ROR"-SO2NHSO2-R'''''' AND RADICALS OF THE FORMULARCH2"-SO2NHSO2-R'''''', R, R" AND R'''''' OCCURING IN SAID LAST FOURRADICALS, INDICATING AROMATIC RADICALS HAVING NOT MORE THAN TEN NUCLEARCARBON ATOMS, SAID ADDITION AGENT BEING PRESENT TO THE EXTENT OF FROM0.1 TO 6 GRAMS PER LITER.